when not at recruitment?

For the first few days of rush, your schedules are usually pretty full, and so you don't have a lot of down time to do anything else. On IWTs I remember getting up at like 6 am to start to get ready and I think didn't get home until 10 pm, and I know during voting some girls don't get home until like midnight. I never heard or saw any girls getting ready to go out on any nights. As someone said above, you're literally dead after rush. As much as you may want to go out to the bars, you're probably extremely tired and you probably have to get up early the next day. After a day of rush, most girls just hang out with their roommates or friends and talk about their days.
Also, all PNMs go to lunch at the dining halls together. Groups are escorted by Rho Chis to the dining halls at specific times. And while PNMs have lunch, the actives also have lunch in their houses. Actives are not allowed to see PNMs anytime other than when they're rushing them. So, no, there are no actives at the dining halls.
There will probably be a few actives checking in at bars to see if there are any PNMs, so as someone else said, I advise any PNMs to not go out. But you never know who you may run into at Target or something. Always be on your best behavior. Just because you're not wearing name tag doesn't mean we don't know who you are.